Seebach: Some teacher certification boards better than others

Saturday, May 13, 2006

The best measure of teachers' effectiveness is how much their students learn, compared with similar students taught by other teachers. Tennessee pioneered this method of value-added analysis, so it was to Tennessee that the American Board for Certification of Teacher Excellence turned to validate its "Passport to Teaching" program for certifying teachers.

This nonprofit board (I'll be talking about another one later on) was started in 2001, and its program is "designed specifically for career changers who want to teach," with a special focus on recruiting potential mathematics teachers. People who enroll in the program are helped to prepare themselves for two examinations, one covering subject matter and the other professional teaching knowledge. Those who pass are recognized as "highly qualified" under the No Child Left Behind Act, and in several states they are eligible to apply for state teaching licenses.

The question the board wanted to answer was how effective their program was in identifying effective teachers. So they recruited a sample of elementary school teachers in three Tennessee school districts and had them take the certification tests. The 55 teachers in the sample who taught in self-contained classrooms also submitted the confidential value-added evaluations they get from the state.

Tough tests. Only 13 teachers passed both of them. That means 42 failed one or both, and remember, all but one or two are licensed teachers, with an average of 14 years of teaching experience. More than half have master's or doctoral degrees.

Maybe, the study notes, they would have done better if they'd had the same opportunity to prepare as participants in the passport program do, but the important thing is that they really need to do better.

The students of the teachers who passed gained 1.04 on a statistical measure of achievement called "normal curve equivalence" relative to those of teachers who failed. The advantage was statistically significant, and it was especially large in mathematics, while the students of the two groups were almost the same in reading. In science and social studies, the advantage favored teachers who passed, but the difference was not statistically significant.

Unfortunately, that's hardly an intuitive measure, but Tennessee also computes a "grade-point average" for students based on their test scores. The average GPA for students of teachers who passed the board's tests was 3.36; for the teachers who failed, it was 2.0.

Which classrooms would you want your children in?

It's a small study, of course, though more will be done. But it is something, which is more than can be said for other tests of teachers' qualifications. "Among the initial teacher licensure examinations in use nationwide, this study is the first designed to validate a licensure examination by the criterion of how much each teacher's students learn," the report says (http://research.abcte.org/files/validity.pdf).

Meanwhile, things are not so rosy for that other board I mentioned, the National Board for Professional Teaching Standards. In 2001, it commissioned a study by William Sanders, who developed the value-added methods Tennessee uses, and his nonprofit SAS Institute.

Well, it's apparently done, but NBPTS so far has chosen not to publish it. There's only a brief overview (www.nbpts.org/research/archive_3.cfm? id=162) on their site, and it is really quite peculiar.

It says, "The most important finding was that 'the amount of variability among teachers with the same NBPTS Certification Status is considerably larger than the differences between teachers of different Status.' " That's hardly a finding at all; it's like saying "the variability in adult height among people of the same sex is considerably larger than the differences between people of different sexes."

Who'd expect anything else? But it is largely irrelevant to the question of which group performs better in the classroom. A study I wrote about last year had already shown that the overlap in performance is so large that more than 40 percent of teachers who have earned national board certification perform worse than the average of those without it (http://www.education-consumers. com/Cunningham-Stone.pdf).

Or as Sanders told the newspaper Education Week, if a school were to choose a board-certified teacher over an otherwise similarly qualified teacher without the credential, it would be "only trivially better than a coin flip."

And given that teachers often spend thousands of dollars earning the credential, and some districts pay them thousands of dollars more per year for having it, it's looking more and more like money down the drain.

The overview certainly gives that impression. "As is common in research, this study encountered many obstacles." And peer-reviewers "noted several areas that may limit the study findings": changes in North Carolina's way of scoring the tests during the study, the fact that there weren't enough national-board certified teachers for robust statistical results, and - very odd, this - in this sample, the students of the board-certified teachers already performed at higher levels, which "may preclude the \[certified] group from exhibiting higher gain scores."

No; high-performing students generally have higher gain scores. That's pretty much what it means, unless the board-certified teachers actually hold them back.

All in all, this appears to be an attempt to discredit bad news before it leaks, which suggests the news is very bad indeed.

Linda Seebach is an editorial writer for the News. She can be reached by telephone at (303) 892-2519 or by e-mail at seebach@RockyMountainNews.com.